Are model trains a necessary part of your daily routine? Yup. Do you become grumpy and irritable if your modeling time is taken away from you? Yup. If you begin building, just a little bit, do you find it hard to stop? Frequently. Do you find yourself growing distant from friends who disapprove of your train habit? Disapprove, you ain't no friend of mine. Do you find yourself needing more and more trains to get the same "fix"? Sometimes. That New Haven freight motor is definitely not essential. When you meet a new person or enter a new room, do you instantly size up his modeling? Why else enter a train room? Does your modelling sometimes get in the way of leading a "normal" life? What's normal? Do you buy trains to make yourself feel better when sad or lonely? Been known to.Dan Drezner found a defense of reading, at least in Greater DeKalb, that is suitable for model railroaders as well.
At least at Chicago, if not in some larger segments of the world, a person who reads books all the time is considered admirable, even if all that is gained by this reading is that the reader is entertained.Chicago is also the place to be for O Scale in the United States, hence this defense generalizes.